Absorption refrigerating apparatus



Sept. 25, 1928. 1,685,340

A. RICHTER ABSORPTION REFRI GERATING APPARATUS Filed 593313.15. 1924 ZSheets-Sheei. 1

lll

Sept. 25, 1928. 1,685,340

A. RICHTER ABSORPTION REFRIGERATING APPARATUS Filed Sept.l5, 1924 I 2Sheets-Sheet 2 Fig.2.

Patented Sept. 25, 1928.

UNITED STATES PATENT OFFICE.

ALFRED RICHTER, OF DOBERITZ, NEAR BERLIN, GERMANY, ASSIGNOR TO A.-G. Fl 'R HANDELS- UNI) INDUSTRIEWERTE GLARUS, OF GLARU'S,

SWITZERLAND.

ABSORPTION REFRIGERATING APPARATUS.

Application filed September 15, 1924, Serial No 737,917, and in Germany September 19, 1923.

This invention relates to a refrigerating apparatus working on the absorption principle, in which from a vessel containing a so-called refrigerating liquid (for instance an aqueous solution of ammonia or spirit of ammonia) the refrigerating medium proper, for instance the ammonia or the spirit of ammonia, is forced out during one period of time by boiling and is thereupon forced into other parts of the apparatus, namely, a condenser, in which the refrigerating medium liquefied and an evaporator, in which the refrigerating medium is evaporated by absorbing heat from the outside. During the next period of time the vessel cooled. so that a greater or less degree of vacuum is pro duced over the liquid, for instance water left over from the boiling and the gases of the refrigerating medium formed in the evapora tor are reabsorbed. The gaseous refrigerating medium must be introduced through the liquid in the vessel at the lowest possiblepoint so that it is forced to flow through the said liquid before it can reach the vacuum above the liquid in the same vessel. The refrigcrating medium will be greedily absorbed by the liquid and at the end of this period of time there will again be present in the vessel a refrigerating liquid, which is saturated with the refrigerating medium, so that boiling can again take place. The liquid in the vessel must be of such a nature that it is c: pable absorbing the refrigerating medium and therefore referred to as the absorption liquid. The ref .erating medium can be absorbed from the evaporator along the 'tomatically at the end of each period (boiling or reabsorbing), and the requisite movable parts were the cause of leakages and breakdowns in the plant. Other apparatus of a known kind worked with immersion bells or other additional devices in the vessel for the refrigerating liquids. In the latter case the space within the vessel is not utilized to the best effect and relatively large quantities of water are required for the boiling operation.

The object of the present invention is to provide apparatus, which has no moving parts and permits of the use of containers for the refrigerating liquid,which are smaller than those used hitherto, so that the heating is more efliciently utilized. According to the invention any number of such contain ers may be used in con'ibiuation and be controlled jointly. Thus, it is possible to use small vessels so that. should they be damaged. the disadvantages caused thereby will be less serious. than where large containers are used.

The invention consists in this, that vessels are used as boilers and, absorbers. which are not in direct communication, but in indirect communication with the other parts of the apparatus (condenser, evaporator and the like) by way of controlling vessels containinc; a liquid and which act as vessels, through which a flow takes place and which. work on the principle of the displacement of the level. the arrangement being such that. when the liquid in them is at a certain level, pipes coming from the steam space and. when the liquid is at another level. pipes connected to as low a point as possible of the liquid space of the main vessel are connected to the other parts of the apparatus, such as the condenser, evaporator and the like. lVhen the level in the controlling vessel is altered. in at least one of the connecting pipes between the main vessol and the controlling vessel (intermediate vessel) the liqni d will be at a different level during the boiling in the main vessel during the reabsorption and will act as a liquid seal. One or more main vessels may be connected to one controlling vessel.

In the accompanying drawings Figs. 1 and 2 show diagrammatically and in section a constructional example. in which a controlline vessel is placed hisrher than the main vesselsand externally of the same, Fig. 1 show ino the boiling period and Fig. 2 the reabsorntion or absorption period.

Figs. and 4. show diagrammatically and in section another constructional example, in

which the controlling vessel is located within the main vessel.

Fig. 8 again representing the boiling period and Fig. t the reabsorption or aosorption period.

In Figs. 1 and 2 A and B are the niain vessels, which contain the refrigerating liquid. (an aqueous solution ol ammonia orspirit of ammonia). 112. '2 2 areqii iea'out or which a con'ibnstihle gas mixture or a coinlnistible iluid [lows in the direction of the arrows, which is ignited during tliebOiIiiig period. 7.1 to a re pipein the main vessels, through which a refrigerating medium flows during the absorption period.

C is a controlling vessel. which acts as an intcrniediatevesself and in which is located a bell-shaped vessel G which only open at its lower side. Pipes (Z (Z coming; from the lowest point ot' the vessel 0 connect'the vessel C to the vertical pipes (Z, wil which communicate with the steam space a of the main vessels A, B at 0. The steam spaces '11; are preferably connected at the highest point by a pipe n. so that the pressures in them must be equal. To the lowest part of the main vessels It and it are connected the branches ot' a pipe 3, the other end of which is connected to he highestpoint of the bell G.

L is a. pipe in the bell G, through which a cooling medium (gas or liquid) flows duringtheabsorption period.

The highestpointof the steam space P oi the vessel C is connected by a pipe L to the other parts of the apparatus (condenser. evaporator and the like).

Preferably a heat insulating cover H is provided, which collects the rising combustion gases of the {lame at the pipes 7)L ,)')L ,.('.Ol1 VtiYStliCll'l. round the contro ling vessel (1 and conducts them away through an escape pipe 2?.

At the commencement of the hoiline period the two main vessels A and B are almost completely filled with the refrigerating liquid. while the vessel 0 is filled only to onethird of its capacity, preferably also wi th: the retrie'erating liquid.

During the boiling period (expulsion period) the ai'aparatus operates in the following; manner (Fig. 1),: i

By heating; the two vessels A and B. by means of any suitable source 0t heat (represented in Fi 1 asgas heating through pipes Nth/INF) the retr'p'eratingmedium ammonia) driven out of. the absorption liquid (water). The re'l rigeratingr uihdiun'i accumulates in the form 0t gas in the space it at the top of the main vessels and. owingto being at a pres- Shll'fiflllfilfi that of the atmosphere. displaces the liquid "from the vessels A and B throu the pi pc .9 into the controlling ves el C (intermediate vessel.) uptil, the level of the liquid has been forced ,down below the openinii's 0 of the pipes Z, (P. As soon as the openineis 0 are free of the liquid, the gaseous reiirigerating medium will flow through the pipes d, d (Z (Z in the direction shown by the arrows to the controlling vessel C, from where they pass into the bell G from below. The bell G becomes tilled with the gases until the liquid in the bell has been forced completely out into the vessel C. T he gases then bubble up through theliquid in the vessel Q into the gas space 1 of the vessel C, tronrwhere they pass through the pipe L into the other parts of the apparatus (condenser, evaporator). l Vhilc this is going; on therewill always be a cohunn of liquid in the pipe 8, the height of which is such that its liquid pressure balances the difference of the pressures in the other parts of the apparatus and in the vapour spaces it. This prevents any more liquid being forced from the vessels A and B into the vessel C, after the commencement of flow through the intermediate'vessel C. V

The cover H forces the coi'nbustion gases to sweep around the controlling vessel C and to help to heat the same. This heating; is further increased by the heat ot'the ,gg'ases flowing through the controlling vessel' C troin the main vessels A and B. By this means most of the refrigerating medium. (ammonia) is driven out of the liquid contained in the controlling vessel C.

The apparatus acts in the following manner during the cooling" period ahsor 'ition period) (Fig. 2) :The source of heat is turned oil and a cooling medium is passed through the cooling pipes Z1 to 707.

Through" the cooling of the solution (air sorption liquid), which contains relatively little ammonia. in the main vessels A and B, the pressure in the latter will be reduced and will fall below the pressure in the rwapotator. Owing to the increased pressure -thus obtained. the gases of the refrigerating medium will pass from the evaporator through the pipe L in the direction shown by the arrows into the controlling),- vessel G and will force the liquid out ot the latter into the bell G, and also into the suction pipes (Z {1 which communicate with the lowest part oi. the controlling vessel C. Liquid is forced into these pipes until a. column of liquid has] been formed. the static pressure ofwhich balances thereupon pass in the direction of the arrows into the bell G' and flowthrough theliquid contained therein. which consequently ab sorbs a correspondingly small amount of the refrigerating medium (ammonia). The greater part of the gases will pass through the pipe 3 int-0 the main vessels A and B at" the lowest point of the same and will thus be forced to How through the whole of the ab sorption liquid in the main vessels A and B on its ay to the spaces 92, so that it will be entirely ahsorl 2d during; its passagzje.

Obviously the pipe 5 will act as an accun'ur later during the boiling period and the pipes (Z d will act similarly during; the cooling period and the liquid zmcuruulated in them will act as liquid seals, which will have the same clhvct as a llltcflttlllt'tll valve.

In the constructional example shown in Figures 3 and l, parts acting in a similar manner are given. the same reference letters as in Figures 1 and 2.

The vesse A, which acts as the boiler and absorber, contains the controlling vessel G, which as the vessel through which the licuid flows, the intermediate vessel, in which s the bell-shaped vessel 9. From the vapour space a in the vessel A a pipe (Z, of large diameter passes upwards am is connected at the top to the pipe rl,,, which opens at m in the vessel (lat the lowest point of the same. Preferably an extension I is provided at the bottom or the vessel. G. that the orifice m of the pipe (1,, is always immersed in the liquid even when the apparatus is inclined. The be l. w is extended upward] in the form of a titiblllill' dome (Z in which are the pipes s and (Z,,, of which the pipe 3 leads to the lowest part ot the liquid space of the vessel A. From the controlling; vessel C a pipe r leads tlu'oufrh the vessel A to the outside to the other parts of the apparatus (the condenser, evaporator and the like). The pipes 70,, ,75 are cooling pipes, through which a cooling' med um flows during the absorption period. Electric heating elements maybe placed in the pipes ]L,, h, in the main vessel A, which will act as the source of heat during'the boiling period. The heat may of course be supplied fron'i other sources of heat, for instance by lllil'lQF-l om the outside or by a liquid or gaseous heat transmitting medium. for instance s tcam. being); passed through the pipes ,0, to K2,, during: the boiling! period in place of the coolingmedium.

The a paratus operates as follows during); the boihn period (Figure 3) The main vessel A is tilled up to about the marl: u, with a refrigerating liquid, tor in stance a high wrceut solution of spirit of ammonia. The controllinn; vessel (l is filled to about one third o'l -its volume with a simila solution. By means of the source of heat :2 portion of the refrigerating medium is driven out ot' the wate and accumulates in the form o'l the vanour space 79, from which. owin its pressure be above that of the atmos ere, it passes throu' the pipe (Z, and

to a suitable height, the height of which column corresponds to the difference of the pressures in the vapour space 79 and in the other parts of the apparatus (evaporator and the like) and balances the same. The column of liquid prevents grases from passing directly out of the main vessel into the intermediate vessel through the pipe 8 and thus acts as a liquid seal during the boiling; period. The emerging at the lowest point or irst accumulate in the bell g and force the liquid in the said bell into the outer vessel G. The gases thereupon pass through the liquid 2?, owing to their pressure being); above that of the atmosphere in the intermediate vessel G, into the vapour space 7) and pass thence in the direction of the arrows through the pipe r to the condenser. In the condenser they are liquefied and accmnulate in an evap orator.

As soon as the boiling period is finished. the cooling period may con'uuence.

During the cooling period (Fi i. the ::1p paratus operates in the following manner:

Owing}; to the boiling vessel A cooling through the action of the coolin water, which flows through the cooling pipes 70,. 70 70 the pressure in the vessel A will fall below that in the evaporator. Hence gases will flow back from the evaporator through the pipe 7'. The pipe 7 first conveys the gases into the vessel G, in. which the returning gases ftorce the liquid into the hell. 7, and. thereupon flow through the liquid. The then rise in the tubular dome (5,, pass at the highest point 00 into the pipe s and are conveyed down the pipe till they reach the lowest point where they enter the vessel A and are distributed in the absorption liquid, thus becominc absorbed.

Dru-inn the cooling period there can be no direct flow 01 the from he vessel G into the vapour space p of the vowel 7r: as a column of liquid accumulates in the pipe (Z, which balances the pressure above atmosi'iherio in the vessel G relative to the vapour space 7? ol the vessel A. while the column of liquid in the pipe #7. which accumulated during; the boiling period, will have sunk. owing; to the reversal of the pressure conditions during; the cooling period.

The continuous functionine' of this hydro static .utrol is en ured more particularly by the tact that the voh ne of liquid in the vessel G is always aiuomatically liept equal. Assiu r tor instauct that through some circumstance liquid should have passed from the controlling vessel G into the vessel A, the liquid le l. in the latter would be raised and during the next boilinr period this liquid would nutoruaticallv r. rn into the controllin (1 the pipe (Z, passes so far into A that the oases cannot escape iur s ace p into the pipe (2,. before the excess of liquid is forced back through the pipe 3 into the controlling vessel G and the level in the main vessel has fallen to the mark 7%,. lthin the converse case, the controlling vessel G should be filled to excess with liquid through any circumstance, as much liquid will remain in the controlling vessel Gr during the first cooling period (Fig. as can lind room in the chamber G with the lomo (1,. The excess of liquid will discharge autoniatically through the pipe 8 into the vessel. A, until the level n, is reached.

The liquid contained in the controlling vessel it} is also utilized for refrigerating purposes, as this vessel is located within. the vessel A and is heated or cooled by the latter.

During the boiling period the pipe 8 again acts an accunu'ilator and during the cooling period the pipe (Z acts as an accumulator in which a sealing liquid accumulates, which has the same action as a mechanical valve.

Having now particularly described and ascertained the nature of said invention and in what manner the same is to be performed, l declare that what I. claim is 1. In an absorption refrigeration apparatus, the combination of an absorber vessel adzqjited to contain a liquid absorbent for the refrigerant, a second vessel likewise adapted to contain a liquid and having a vapor outlet at the top thereof, an inverted receptacle disposed in said second vessel, pipes providing communication between said ves sels, one of said pipes connecting the top or vapor space of said absorber vessel with the second vessel of a point below the liquid level therein, said pipe being so disposed as to act as a liquid seal and another of said pipes establishing communication between the absorber vessel, at a point below the liquid level therein and within the inverted receptacle, and the second vessel at a point above the point at which the first mentioned pipe terminates in the second vessel, said pipe being so disposed as to act as a liquid seal.

2. In an absorption refrigeration apparatus, the combination of an absorber vessel adapted to contain a liquid absorbent for the refrigerant, a second vessel likewise adapted to contain a liquid and having a vapor outlet at the top thereof, an inverted receptacle disposed in said second vessel, pipes providing coinnumication between said vessels, one of said pipes connecting the top or vapor space of said absorber vessel with the second vessel at a point below the liquid level therein and beneath the opening of the inverted receptacle, said pipe being so disposed as to act as a liquid seal and another 01' said pipes 'establishing communication between the absorber vessel, at a point below the liquid level therein and within the inverted receptacle, and the second vessel atr a. point above the point at which the first mentioned pipe terminates in the second vessel, said pipe being so disposed as to act as a liquid seal.

3. in an absorption refrigeration apparatus, the combination of: an absorber vessel, adapted to contain a liquid absorbent for the refrigerant, a second vessel disposed within said absorber vessel likewise adapted. to contain a liquid and having a vapor outlet at the top thereof, an inverted receptacle within said second vesse pipes providing coinunication between said vessels, one of said pipes connecting the top or vapor space of said absorber vessel and terminating in said sec ond vessel at a point below the liquid level therein, said pipe being so disposed as to act as a liquid seal, and another of said pipes establishing coninuinication between the absorber'vcssel, at a point below the liquid level therein and within the inverted receptacle, and the second vessel at a point above the point at which the first mentioned pipe terminates in the second vessel, said. pipe being so disposed as to act as a liquid seal.

l. In an absorption refrigeration appara tus, the combination of an absorber vessel, adapted to contain a liquid absorbent for the refrigerant, a second vessel disposed within said absorber vessel likewise adapted to contain a liquid and having a vapor outlet at the top thereof, an inverted receptacle within said second vessel, pipes providing communication between said vessels, one of said pipes connecting the top or vapor space of said absorber vessel .and terminating in said second vessel at a point below the liquid level therein, and beneath the opening of the inverted receptacle, said pipe being so disposed as to act as a liquid seal, and another of said pipes establishing communication between the absorber vessel, at a point below the liquid level therein and within the in verted receptacle, and the second Vessel at a point above the point at which the first mentioned pipe terminates in the second vessel, said pipe being so disposed as to act as a liquid seal.

ALFRED RICHTER. 

